Sports Equipment

ABSTRACT

An item of sports equipment to be fastened to a person&#39;s foot, the sports equipment including a rolling or sliding member by which the sports equipment can be rolled or slid along a ground surface, wherein the rolling or sliding member includes a front portion and a rear portion, wherein the front portion includes a roller or a sliding surface for the ground surface, and the rear portion includes a roller or a sliding surface for the ground surface, wherein the front portion and the rear portion are connected to a crosspiece.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Phase application of PCTInternational Application No. PCT/EP2011/002230, filed May 5, 2011,which claims priority to German Patent Application No. 10 2010 020253.3, filed May 11, 2010, the contents of such applications beingincorporated by reference herein.

FIELD OF THE INVENTION

The invention relates to an item of sports equipment which is arrangedon or fastened to a person's foot for its intended use. The sportsequipment can for example be a sliding board or snow sliding board, inparticular an alpine ski. In principle, however, the sports equipmentcan also be a cross-country ski, a roller ski or an in-line skate.

BACKGROUND OF THE INVENTION

A multitude of different alpine skis are known from the prior art.Modern skis are configured as so-called carving skis. One essentialfeature of a carving ski is its relatively large sidecut. This meansthat the ski is significantly wider at its front and rear ends thanbetween the ends, such as for example in the region of the binding,which is the narrowest point or point of greatest sidecut. Thisdetermines the sidecut depth. This depth can be measured if the ski isput on edge, on a level surface, by 90° about its longitudinal axis andlies on its widest points at the front and rear end. The distancebetween the narrowest point of the ski and the level surface correspondsto the sidecut depth. Between the bearing points, the lateral flank ofthe ski follows a curve for which a radius can be calculated as afunction of the distance between the bearing points and the sidecutdepth. In the case of carving skis, this radius usually equates tobetween 10 and 20 m, but can also be more or less than this. Fordesigning the shape of the lateral flank of the ski and/or forascertaining the radius of the lateral flank, the curve radius of theideal motion curve and the desired motion speed are selected. From this,it is possible to ascertain the centrifugal force and therefore theinclination angle of the skier and the skis towards the interior of thecurve for stable turning. This determines the carving angle by which theski is put on edge about its longitudinal axis. If one imagines a skiwhich has a constant width and is flexed about its transverse axis ontothe radius of the motion curve, then the intersecting edge between theski and the ground surface—which is assumed to be level—determines thedesired shape of the lateral flank of the ski. Carving skis thereforecarve particularly well.

Other features of a carving ski are its flexibility about the transverseaxis, which is predetermined by its flexural rigidity about thetransverse axis, and its ability to twist about the longitudinal axis,which is predetermined by its torsional rigidity about the longitudinalaxis of the ski. What is generally desired is flexibility of the skiabout its transverse axis combined with a high torsional rigidity of theski. Due to the design of the ski, high flexibility combined with hightorsional rigidity cannot usually be realised simultaneously. Thebinding in combination with the ski boot also influences, i.e. reduces,the flexibility of the ski.

Referring to FIGS. 1 a to 1 c, the behaviour of known skis underdifferent load conditions shall be explained. The ski in FIG. 1 a has noload, wherein it can be seen that due to its prestress, the ski 1 isconcavely arched on its sliding surface between the front and rear ends.If the ski 1 is put on edge, as in FIG. 1, and the ski 1 is pressedagainst a flat ground surface with a force F, it will bow convexly. InFIG. 1 b, the line of application of the force F—which is applied at theskier's centre of gravity—passes through the design point K which hasbeen assumed to be the force application point in the design of the ski.The ski 1 is therefore under a load, as is assumed in the design. If theedge of the ski conforms to the ground surface, then it is not deformedany further, irrespective of the magnitude of the force F.

While skiing, the skier does not usually keep their centre of gravityexactly and constantly over the design point K. The skier's centre ofgravity is instead situated in front of or behind the design point, suchthat the force F is applied at an offset in relation to the designpoint. If the force F applied at the centre of gravity is offset towardsthe rear in the longitudinal direction in relation to the design point,then the angular speed during motion will be increased by the factor ofthe motion curve. If the force is offset towards the front in thelongitudinal direction in relation to the design point K, then theangular speed during motion will be reduced by the factor of the motioncurve. The force F which is offset in relation to the design point Kgenerates a moment which is dependent on the distance between the forceline of the force F and the design point K. This moment raises the skibetween the design point K and the front end such that the edge nolonger lies on the ground surface at this point, or at least relievesthe ski at this point such that the edge no longer presses onto theground surface with the required force. The ski will therefore no longerfollow the ideal motion curve.

It is therefore an object of the invention to provide an item of sportsequipment which can be strapped onto a foot and which enables improvedmotion characteristics.

SUMMARY OF THE INVENTION

This object is solved by the subject matter as describe in thedescription and illustrated in the figures.

The invention proceeds from an item of sports equipment to be fastenedto a person's foot. It is for example possible to provide one such itemof sports equipment for each foot or to provide one shared item ofsports equipment for both feet. The sports equipment can for example bea snow sliding board, such as for example a ski, particularly preferablyan alpine ski. Alternatively, the invention can also be used with rollerskis or in-line skates. The sports equipment can be able to be fastenedto the person's foot by means of a boot. The boot can be a separate partwhich is connected to the sports equipment, or the sports equipment cancomprise the boot.

The sports equipment comprises a means for contact with the groundsurface, which can be referred to as the ground surface contact means.This means can be a rolling means or a sliding means. Using the groundsurface contact means, the sports equipment can be able to be moved, inparticular rolled or slid, along a ground surface in a contact. Therolling or sliding means can comprise a front portion and a rearportion, wherein the front portion comprises a roller or a slidingsurface for the ground surface, and the rear portion comprises a rolleror a sliding surface for the ground surface.

The front portion is the portion which is arranged in front of the rearportion in the intended direction of motion. The intended direction ofmotion preferably corresponds to the forward movement of the user of thesports equipment. The front portion and the rear portion are parts whichare preferably separate from each other and are preferably configured tobe elongated. The longitudinal axis of the front portion and thelongitudinal axis of the rear portion can preferably be aligned witheach other and can in particular form the longitudinal axis of thesports equipment. The front portion can form a mount for at least oneand preferably two rollers or a sliding surface and in particular anengaging edge. The same correspondingly applies to the rear portion.

If the ground surface contact means is a rolling means, the frontportion—which is in particular formed in the shape of a mount—can formor comprise a bearing for the at least one roller and comprise at leastone roller which can be rotated relative to the front portion. The samecorrespondingly applies to the rear portion. Slide bearings or ballbearings which can be formed from metal, plastic or ceramic can beprovided as the bearing. The running surfaces of the rollers preferablycomprise a plastic or rubber material which on the one hand offers goodrolling-off characteristics and on the other hand prevents the rollersfrom slipping away laterally. In particular, the front portion and/orthe rear portion can respectively comprise at least two rollers. Thefront and/or rear portions are respectively supported in thelongitudinal direction at two points of contact on the ground surface.The first roller forms the first point of contact with the groundsurface, and the second roller forms the second point of contact withthe ground surface. The at least two rollers of one portion and inparticular the at least two rollers of the other portion are arrangedone behind the other in the longitudinal direction. In particular, therollers of the front and rear portions roll off on a shared line.

In particularly preferred embodiments, the ground surface contact meansis a sliding means. A sliding surface is arranged on the lower side ofthe front portion which is formed in the shape of a mount. The sameapplies to the rear portion. The sliding surface can be formed by aplastic material or a metal which in particular forms a low coefficientof friction with snow or ice. The sliding surface can be definedlaterally, i.e. along the longitudinal axis, in particular on both sidesby engaging edges which can preferably be formed from metal, inparticular steel. It would however in principle also be possible toprovide only one engaging edge, for example on the inner side, i.e.where there is a separate item of sports equipment for each foot, on theflank pointing towards the other item of sports equipment. When thesports equipment is put on edge about the longitudinal axis, theengaging edges can enter into engagement with the ground surface. Theengaging edges form the transition between the sliding surface andlateral flanks extending along the longitudinal direction of the frontand/or rear portion. The engaging edges are preferably arranged on bothsides of the sliding surface and/or laterally enclose the slidingsurfaces. The front portion and the rear portion are preferablyconfigured in the shape of boards or sliding boards, i.e. the thicknessof each of the front portion and rear portion is small as compared totheir length and/or width. In particular, the front portion and the rearportion can be configured in the shape of skis.

The front portion and the rear portion can preferably be elasticallydeformed about their transverse axis, i.e. the axis which isperpendicular to the longitudinal axis and parallel to the groundsurface and/or sliding surface, in particular to such an extent that thefront portion and the rear portion can conform to a path arranged on theground surface. It is generally preferred if the front portion and rearportion can be elastically reshaped such that the engaging edges canconform to the ground surface or the path when the sports equipment isput on edge.

It is preferred if the front portion widens, in particular constantly,from its end which points towards the rear portion to its opposite, i.e.front end. The region at the front end of the front portion is wider inthe direction of the transverse axis than the region at the rear end ofthe front portion. The rear portion can widen, in particular constantly,from its end which points towards the front portion to its opposite, inparticular rear end. The region of the front end of the rear portion canexhibit a smaller width in the direction of the transverse axis than theregion at the rear end of the rear portion. The width of the rear endregion of the rear portion can preferably be smaller than or also largerthan or as large as the width of the front end region of the frontportion. The front portion and rear portion are preferably arranged withrespect to each other such that their engaging edges lie on a sharedcurve, in particular having a shared radius.

The arrangement consisting of the front portion and the rear portion canexhibit a sidecut which—between the bearing points formed in the regionof the front end of the front portion and in the region of the rear endof the rear portion—is at its largest in the region of the rear end ofthe front portion or in the region of the front end of the rear portion.In particular, the sidecut depth is at its largest in this region. Thesidecut depth can for example be 32 mm, thus forming a radius of 10 m ata distance between the bearing points of 1600 mm. The sidecut or sidecutdepth onto the curve on which the engaging edges of the front portionand the rear portion lie can be at its greatest in the region in whichthe front and rear portions point towards each other. In other words,the front and rear portions of the sports equipment could be obtained bycutting through a conventional carving ski in the region of its smallestwidth transverse to the longitudinal axis, in particular along thetransverse axis.

In accordance with the invention, the front portion and the rear portionare connected to a crosspiece. The crosspiece can be a part which isseparate from the front and rear portions. The crosspiece preferablyspans a region in which the front and rear portions point towards eachother, in particular without being fastened to this region and/or with agap between this region or the front and/or rear portion. In embodimentsin which the ground surface contact means is a sliding means inparticular, the crosspiece exhibits a greater moment of resistance toflexing about the transverse axis than the front and rear portions. Thecrosspiece also exhibits a higher torsional capacity than the front andrear portions. The crosspiece can therefore be regarded as rigid ascompared to the front and rear portions. Due to the greater rigidity ofthe crosspiece, torsional moments generated when turning can thereforebe channelled via the relatively rigid crosspiece into the front andrear portions. This results in a significantly reduced deformation ofthe ski and/or the front and rear portions as compared to a standardski, whereby the edge engagement is maintained during turning. Forconventional carving skis have the problem that due to their largesidecut and high flexibility about the transverse axis, a torsion isgenerated which causes the region of the binding to be put on edge at agreater angle than the region of the front end and rear end of the ski.During extreme turning or in the event of skiing errors, i.e. when thecentre of gravity is shifted towards the front or towards the rear inrelation to the design point, the ski can slip away, which can even leadto a fall.

In generally preferred embodiments, the crosspiece is fastened to thefront portion between the end which points towards the rear portion andits opposite end, in particular via a joint, and is fastened to the rearportion between the end which points towards the front portion and itsopposite end, in particular via a joint.

The crosspiece can in particular be connected or fastened to the frontand rear portions via the joints only. The region of the crosspiecewhich is arranged between the joints is preferably self-supporting, i.e.substantially disconnected from the first and second portions, or spansthe region between the joints in a self-supporting manner. However, thisshould not necessarily exclude the possibility of the region of thecrosspiece arranged between the joints coming into contact with thefront and rear portions or the joint arranged between these portions. Aspring element and/or a damping element could for example be arrangedbetween the self-supporting portion of the crosspiece and the frontportion, the rear portion and/or the joint.

The joint which connects the crosspiece to the front or rear portion ispreferably a pivoting joint. The pivoting joint can comprise at leastone or only one rotational degree of freedom. The pivoting joint ispreferably connected rigidly about the longitudinal axis to the frontand rear portions for a pivoting movement of the crosspiece relative tothe front and rear portions, in particular without a rotational degreeof freedom about the longitudinal axis. The joint is preferablyconfigured such that it permits a pivoting movement between thecrosspiece and the front portion and between the crosspiece and the rearportion about the transverse axis, in particular with a rotationaldegree of freedom about the transverse axis. The pivoting axis of therespective pivoting joint is therefore parallel to the transverse axis,i.e. parallel to the ground surface, and transverse to the longitudinalaxis of the sports equipment. The pivoting joint could in principlepermit a pivoting movement between the crosspiece and the front portionand between the crosspiece and the rear portion about the vertical axis,although this is less preferred. It is therefore particularly preferredif the pivoting joint permits a pivoting movement about the transverseaxis only. Connecting the front and rear portions to the crosspiece bymeans of pivoting joints which can be pivoted about the transverse axisenables the flexural rigidity of the system to be reduced andcorrespondingly adjusted, irrespective of the torsional rigidity. Inparticular, this ability to pivot means that the rollers or engagingedges better follow the ideal motion curve during turning.

Another advantage of the arrangement of the pivoting joints describedabove is that shifting the force of the skier exerted on the crosspiecetowards the front or towards the rear along the longitudinal axis onlyincreases or reduces the reaction forces on the front pivoting joint andthe rear pivoting joint. The transmission of a moment about thetransverse axis from the crosspiece to the front and rear portions issubstantially prevented or at least reduced by means of the pivotingjoints. The pivoting movement could for example be damped by means of adamping member which is arranged kinematically between the crosspieceand the front portion and/or between the crosspiece and the rearportion. Correspondingly, a spring could also impede the pivotingmovement and/or transmit torque about the transverse axis from thecrosspiece to the front portion and/or rear portion. To this end, thespring would likewise be arranged kinematically between the crosspieceand the front portion and between the crosspiece and the rear portion.

In the design of the sports equipment, a separate design point can beprovided for the front portion, and a separate design point can beprovided for the rear portion. By configuring the sports equipment toinclude the crosspiece, the line of application of the reaction forceexerted on the front portion can pass through the design point. To thisend, the pivoting joint is fastened to the design point. The samecorrespondingly applies to the rear portion. Since the forces thenconstantly act into the design point, and the transmission of momentsabout the transverse axis from the crosspiece to the front and rearportions is at least reduced, a reliable edge engagement or rollercontact is constantly ensured, since the engaging edge or the rollers ofthe front and rear portions conform(s) to the motion curve, even afteronly a relatively small minimum force has been reached for this purpose,when the sports equipment is tilted upwards about the longitudinal axis,irrespective of the force.

The front design point or the front joint is arranged in the region ofthe rear two thirds, in the middle third or in the rear half of thefront portion in relation to the longitudinal axis. The rear designpoint or the rear joint is preferably arranged in the region of thefront two thirds, in the middle third or in the front half of the rearportion in relation to the longitudinal axis. The agility of the sportsequipment during turning can be influenced by the position of the jointsin the front portion and rear portion.

In principle, it would seem possible for the ends of the front portionand rear portion which project towards each other to be connected toeach other in one part. The front portion and rear portion could thenform a shared mount, in particular a ski or roller mount, on which thecrosspiece is placed in the way described above.

A moment could be transmitted from the front portion to the rear portionand vice versa by this arrangement. If this is to be prevented or atleast reduced, the ends of the front portion and the rear portion whichproject towards each other can be connected such that the connectionexhibits a lower flexural rigidity about the transverse axis than thefront portion and the rear portion. It would then for example bepossible to manufacture the front and rear portions integrally, whereinthe part which connects the ends, which can be referred to as a joint,is designed to exhibit a very low flexural rigidity. An example of thiswould be the arrangement of suitable fibre-reinforced plastics such asfor example aramide fibre reinforced plastics which exhibit low rigidityand simultaneously high elastic deformability.

Alternatively, such a joint could be configured in the form of a hinge,wherein the front and rear portions respectively comprise parts of thehinge which interlock and are connected for example by means of a bolt.One portion can for example comprise a hinge part featuring at leastone, for example two sleeve portions which are arranged in alignment andspaced with respect to each other. A hinge part arranged on the otherportion and featuring at least one sleeve part can be arranged inalignment with the at least one hinge part of the first portion, inparticular between the two sleeve parts, wherein the hinge parts arefixed to each other by means of a screw or bolt which is insertedthrough the sleeve parts of the two portions. The advantage of a hingeis that the joint only permits a pivoting movement about one pivotingaxis between the front portion the rear portion. This for exampletransmits torsional moments about the longitudinal axis from the frontportion to the rear portion and vice versa, while flexural moments aboutthe transverse axis are not transmitted. If torsional transmission isnot desired, a ball joint which permits torsional movements and pivotingmovements can be used instead of a hinge.

In another configuration, the ends of the front portion and rear portionwhich project towards each other can be connected to a flexible beltwhich can for example be formed from leather or plastic or from metal.The belt can for example be integrated, for example worked, into thefront and/or rear portion during manufacture. Alternatively, the beltcan be fastened to the front and rear portions using separate fasteningoptions, such as for example by means of a rivet, screws or an adhesiveconnection. The belt can for example be a fabric belt.

In general terms, the means which connects the ends which point towardseach other can form a flexible or elastic connection. The means can forexample comprise or be formed from a metallic and/or elastomericmaterial, such as for example rubber or natural rubber, and/or aleather-like material and/or a duroplast or thermoplast. A compositematerial which forms the connecting means can for example be formed fromat least one or two of these materials.

The connection between the ends of the front and rear portions whichpoint towards each other could in principle comprise a spring memberand/or damping member. The magnitude of the moment about the pivotingaxis which is to be transmitted can be adjusted to almost any value bythe spring member. Pivoting movements which the front and rear portionscan perform relative to each other can be damped by the damping member.

In advantageous developments, the sports equipment can be folded up,enabling it to be transported in a space-saving way. In particular, thetransport length of the sports equipment can be reduced relative to itsoperational length.

In preferred embodiments, the crosspiece is connected to the frontportion by a front fastening means, wherein the fastening means isconfigured such that the crosspiece can be detached from the frontportion. Alternatively or additionally, the crosspiece can be connectedto the rear portion by a rear fastening means, wherein the fasteningmeans is configured such that the crosspiece can be detached from therear portion. In particular, one of the front fastening means and rearfastening means can be detachable, while the other of the frontfastening means and rear fastening means is non-detachable. It is alsofor example possible for both fastening means to be non-detachable.Preferably, the front fastening means and rear fastening meansrespectively form the joint described above, in particular the pivotingjoint for connecting the crosspiece to the front portion and the rearportion.

The crosspiece can in particular comprise the means by which the sportsequipment can be fastened to a person's foot. The means can inparticular be a boot or a binding with which a boot can be fastened tothe crosspiece. The front and/or rear fastening means can in particularbe configured as a safety binding which releases the crosspiece formovement when a maximum load is exceeded. When the maximum load isexceeded, such as for example in the event of a fall, the crosspiece candetach from the front and/or rear portion or at least move far enoughthat the load is reduced, such that injury to the user is prevented.

In particularly preferred embodiments, one of the front portion and rearportion can be connected to the crosspiece such that it can be pivotedabout two pivoting axes, and the other of the front portion and rearportion can be connected to the crosspiece such that it can be pivotedabout one pivoting axis, in particular only one pivoting axis. Inparticular in an embodiment in which the ends of the front and rearportions which point towards each other are connected to each other, inparticular such that they are fixed against shifting but can be pivoted,it is advantageous if one of the front joint and rear joint can bepivoted about two pivoting axes, since this can compensate for changesin length when the first and second portions conform to the motion curveduring turning. As an alternative to a joint featuring two pivotingaxes, a joint—in particular, a pivoting and sliding joint—could beprovided which on the one hand permits a pivoting movement about oneaxis and on the other hand permits a shifting movement between thecrosspiece and the corresponding portion, in particular transverse orperpendicular to the pivoting axis or in the direction of thelongitudinal axis of the portion.

A damping element, in particular one made of rubber, can in particularbe arranged between the crosspiece and the front portion and between thecrosspiece and the rear portion. The damping element can in particularbe arranged between the front fastening means and the front portion andbetween the rear fastening means and the rear portion.

At least one of the front end of the front portion and the rear end ofthe rear portion can be raised and form a so-called shovel. If only oneof the ends is raised, the sports equipment is substantially designedfor motion in one direction only, i.e. in the direction in which theshovel points. If both ends are fitted with shovels, then motion ispossible in both directions, i.e. forwards and backwards, using thesports equipment.

The invention has advantages in the manufacture of the front and rearportions, in particular when they are designed for a sliding contact. Inconventional skis, the sliding surfaces between the front and rear endshave to be curved or concave and exhibit a corresponding prestress. Thisproves to be complicated when manufacturing conventional carving skis,since the cross-sections of the ski change significantly over theirlength due to the large sidecut. In the sports equipment in accordancewith the invention, the front portion and the rear portion can managewithout prestress. Alternatively, however, they can also be prestressed.Correspondingly, the sliding surface of the front portion and/or rearportion can be level or concavely curved when the sports equipment hasno load. Since prestress is not mandatory, the front and rear portionscan be manufactured by means of methods which are more cost-effectivethan with conventional skis. One such method is for example aninjection-moulding method in which for example the edges which are madeof steel are inserted into a corresponding die, and a plastic which canfor example be fibre-reinforced is injected around them.

Another invention relates to the structure of a front or rear portion asdescribed in this document, in particular a ski portion, or a slidingboard, in particular a snow sliding board, preferably a ski, for examplea ski as shown in FIGS. 1 a-c. This invention can constitute anadvantageous development of the sports equipment described above orsubject matter which is independent of the sports equipment describedabove.

It is an object to specify a sliding board which is simple in design andcost-effective to manufacture, and a corresponding manufacturing method.

The elongated front and/or rear portion in the shape of sliding boards,in particular the ski portion, or the sliding board can comprise anupper tension-compression belt and a lower tension-compression beltwhich is spaced from the upper tension-compression belt, wherein theupper and lower tension-compression belts are encased in a plastic bymeans of plastic injection-moulding. This forms a shear-resistant bondbetween the tension-compression belts and the plastic, whereby embodyingthe tension-compression belts can significantly influence the flexuralrigidity of the portion as compared to an embodiment with notension-compression belts. If the portion is flexed about a flexing axiswhich is perpendicular to the longitudinal direction and parallel to thesliding surface, a neutral fibre is created between the upper and lowertension-compression belts. Within the technical-mechanics context ofelastostatics, “neutral fibre” refers to the zone of a beamcross-section which does not change in length during a flexing process.The flexural stress in this zone is zero.

The area moment of inertia and therefore the flexural resistance of thesliding board can be increased by increasing the distance between one orboth belts and the neutral fibre or by increasing the cross-sectionalarea of one or both belts. The flexural resistance of the ski can bereduced by reducing the distance between one or both belts and theneutral fibre or by reducing the cross-sectional area of one or bothbelts.

The upper and/or lower tension-compression belt can for example beformed from plastic, such as for example fibre-reinforced plastic, ormetal such as for example an aluminium or steel alloy and can inparticular be able to be both tensioned and compressed. The upper and/orlower tension-compression belt can be formed in the shape of a plate andfor example formed from sheet metal.

The injection-moulded material is preferably a plastic, such as forexample a duroplast or preferably a thermoplast. The plastic can befoamed or unfoamed.

In order to improve the bond and shear resistance, the upper and/orlower tension-compression belt can comprise a multitude of cavities, inparticular perforations, into which the injection-moulded plastic isintroduced or into which the injection-moulded plastic was introduced asthe composite was being manufactured. The cavities permeate the beltfrom its upper side to its lower side, i.e. in the direction of itsthickness, in particular its sheet metal thickness or plate thickness.The belts can therefore be formed in the manner of a perforated sheet.The cavities or at least some of them can for example be circular,elliptical or oval or can exhibit another, preferably rounded,non-circular shape. These shapes enable an advantageous stressdistribution, which is improved even further if the longest extent ofthe cavity extends approximately in the direction of the longitudinaldirection of the sliding board. The main axis of an elliptical cavity orperforation can for example point approximately in the direction of thelongitudinal direction of the sliding board.

The cavities of the upper and lower tension-compression belts or thecavities of engaging edges can be manufactured by being punched out. Theupper and lower tension-compression belts can be manufactured by aseparating method, in particular punching, or a separating and reshapingmethod, in particular flexural punching, or by another method known tothe person skilled in the art.

The upper tension-compression belt and the lower tension-compressionbelt can be pieces which are separate from each other or can be formedin one piece. If the belts are separate, they are in particularseparated from each other by the injected plastic. If the belts areformed in one piece, they can in particular be connected by connectingportions which permeate the neutral fibre. The connecting portions cancomprise a multitude of cavities which can be embodied as specified forthe cavities of the tension-compression belts. The connecting portionsare preferably arranged transverse to the sliding surface of the slidingboard.

The upper tension-compression belt or the plane in which the uppertension-compression belt lies, and the lower tension-compression belt orthe plane in which the lower tension-compression belt lies, arepreferably arranged approximately parallel to the sliding surface.

The sliding board can comprise engaging edges, in particular steeledges, which preferably comprise cavities, in particular perforations.The cavities can be formed as described for the tension-compressionbelts. The cavities can overlap, in particular be congruent, with thecavities of the lower tension-compression belt. The engaging edges canbe fused or soldered or connected via a connecting layer to the lowertension-compression belt or can abut against it. An adhesive is forexample suitable as the connecting layer. The connecting layer existseven before the adhesive is injected. The engaging edges can thus beinserted into the injection-moulding die as one part together with thelower tension-compression belt when the sliding board is manufactured.The cavities preferably exhibit the same raster and/or size and/or shapeas cavities of the lower tension-compression belt, which advantageouslyenables an unobstructed flow of the plastic between the upper side andlower side of the composite consisting of the lower tension-compressionbelt and the engaging edges. These cavities of the lowertension-compression belt are in particular arranged for example 1 to 10mm away from the periphery of the lower tension-compression belt alongthe longitudinal direction and in the peripheral regions of the lowertension-compression belt.

The upper side of the sliding board, i.e. the side facing away from thesliding surface, can optionally comprise a faceplate which can beprovided with a pattern or with no pattern on its visible side. Thefaceplate can exhibit mechanical properties which are negligible withrespect to the flexural rigidity and/or torsional rigidity of thesliding board or which contribute to the flexural rigidity and/ortorsional rigidity of the sliding board. The upper side or the materialof the faceplate is configured such that it exhibits a suitable adhesionfor being printing on or other technologies for manufacturing a pattern.The upper side of the faceplate can alternatively or additionallycomprise a structure which predominantly serves to furnish opticalproperties. The faceplate can be manufactured by injection-moulding oneor more materials such as for example one or more plastics and cantherefore be an injection-moulded part which however already existsbefore the plastic in which the tension-compression belts are encased isinjected.

The faceplate can comprise projections, in particular ribs, which areanchored in the injected plastic and/or can comprise projections whichserve as spacers for the upper tension-compression belt. One or moreprojections of the faceplate can serve as both anchors and spacers. Theinjected plastic can be arranged between the upper tension-compressionbelt, or a plane in which the upper tension-compression belt lies, andthe faceplate. The projection or projections can be anchored in theplastic during the process of manufacturing the sliding board, byinjection-moulding plastic. The projections which serve as spacers serveto hold the upper tension-compression belt at a distance from thefaceplate while the sliding board is being manufactured, such that theplastic can be dispersed between the faceplate and the uppertension-compression belt and/or can flow through the cavities of theupper tension-compression belt. In embodiments with no faceplate, theinjection-moulding die in which the plastic is injected around the upperand lower tension-compression belts and preferably also the engagingedges can comprise the projections which serve as spacers for the uppertension-compression belt.

The injected plastic can be arranged between the uppertension-compression belt, or a plane in which the uppertension-compression belt lies, and the lower tension-compression belt ora plane in which the lower tension-compression belt lies. The injectedplastic can be arranged between the lower tension-compression belt, or aplane in which the lower tension-compression belt lies, and the slidingsurface.

The sliding board can therefore exhibit the following structure from topto bottom in relation to its height or thickness which is perpendicularto the length and width of the sliding board:

-   -   optionally, a faceplate or a patterned element comprising        projections or ribs;    -   the injection-moulded plastic;    -   the punched or perforated upper tension-compression belt;    -   the injection-moulded plastic and as applicable a connecting        portion of the upper and lower tension-compression belts;    -   the punched or perforated lower tension-compression belt;    -   engaging edges, provided with cavities or perforations, in the        peripheral region of the sliding board or lower        tension-compression belt;    -   the injection-moulded plastic.

The sliding board can be manufactured using the following steps.

If provided, the faceplate—in particular, a patterned element—isinserted into an injection-moulding die, wherein at least one spacer inthe form of one of the aforementioned projections is for exampleprovided for the upper tension-compression belt.

If provided, a tip protector or a part of the joint—in particular,hinge—for the front end and/or a protector or a part of the joint—inparticular, hinge—for the rear end of the sliding board can optionallybe inserted into the injection-moulding die. Dies for the faceplate, thetip protector and the protector for the rear end, into which therespective part can be inserted, can be provided in theinjection-moulding die. If one of the faceplate, the tip protector andthe protector for the rear end is not inserted as a separate part, theinjection-moulding die can comprise corresponding die portions in whichthese parts are formed during injection-moulding.

In preferred embodiments, a part of the joint can be formed duringinjection-moulding, i.e. the part of the joint is manufactured duringinjection-moulding. Alternatively, the part of the joint can be aconstituent of the upper tension-compression belt or a constituent ofthe lower tension-compression belt. To this end, the front or rear endof the upper or lower tension-compression belt can form a part, such asfor example a sleeve or an eyelet, which is manufactured by reshaping,in particular flexing. In another alternative, the part of the joint canbe inserted into the injection-moulding die before injection-moulding,wherein subsequent injection-moulding at least partially injects theplastic around the part of the joint or at least partially anchors thepart of the joint in the plastic.

The upper tension-compression belt is inserted into theinjection-moulding die, in particular into a part of theinjection-moulding die which is intended for the upper side of thesliding board, and fixed. The lower tension-compression belt, to whichthe engaging edges are fastened, is simultaneously or subsequentlyinserted into the injection-moulding die, preferably together with theengaging edges, in particular into a part of the injection-moulding diewhich is intended for the lower side of the sliding board. Once theseparts have been inserted, the injection-moulding die can be sealed.

Plastic which is provided in a free-flowing state, in particular aheated thermoplast, is injected into the injection-moulding die, suchthat the plastic is injected around the upper tension-compression beltand the lower tension-compression belt. The free-flowing plastic is forexample injected through an opening, in particular a hole in the uppertension-compression belt which is preferably larger than the cavities ofthe upper tension-compression belt, between the lowertension-compression belt (or its plane) and the uppertension-compression belt, or below the upper tension-compression belt,in particular towards the lower tension-compression belt. Thefree-flowing plastic is divided into a front plastic flow (in relationto the longitudinal direction of the sliding board) towards a front endor the tip, and a rear plastic flow (in relation to the longitudinaldirection of the sliding board) towards a rear end, wherein the uppertension-compression belt is advantageously pressed against the spacersof the injection-moulding die or faceplate. If a lowertension-compression belt which is separate from the uppertension-compression belt is provided, the tension-compression belts canbe pressed or held apart by the plastic flows.

The divided plastic flows are respectively pressed through a multitudeof the cavities of the upper tension-compression belt and/or lowertension-compression belt onto the other side of the upper and/or lowertension-compression belt, i.e. onto the lower side of the lowertension-compression belt or between the sliding surface and the lowertension-compression belt, whereby the plastic also flows through thecavities of the engaging edges and encases the engaging edges andpreferably also forms the sliding surface, and onto the upper side ofthe upper tension-compression belt, whereby the plastic encases theprojections of the optionally provided faceplate which serve as anchorsor forms the upper side of the sliding board.

The injection-moulding die can comprise one to five recesses orprojections which extend in the longitudinal direction of the slidingboard and are configured such that they form corresponding projectionsor recesses on the sliding surface of the sliding board, whichadvantageously increases the directional stability of the sliding boardwhen it is in use. If they are arranged in the edge region of thesliding board, the recesses or projections can be arranged parallel tothe edges or the sidecut curve of the sliding board, such as for exampleone projection or recess for each of the left-hand and right-hand edgeof the sliding board.

Once the injected plastic has solidified, for example by cooling theinjection-moulding die, the injection-moulding die can be opened and thesliding board removed or ejected.

Such a sliding board has the following advantages over already existingtechnologies:

-   -   a lower number of parts;    -   a shorter manufacturing cycle per sliding board, i.e. about two        minutes instead of 20 to 30 minutes as before;    -   almost no cuttings, waste material or cut-off material;    -   apart from sharpening the engaging edges, the sliding board does        not need to be abraded after it has been removed from the        injection-moulding die.

BRIEF DESCRIPTION OF THE DRAWINGS

The inventions have been described on the basis of a number ofadvantageous embodiments. In the following, the inventions are describedon the basis of figures. Features thus disclosed, each individually andin combination, advantageously develop the inventions. There is shown:

FIGS. 1 a to 1 c a conventional ski, under different load conditions;

FIGS. 2 a to 2 c an item of sports equipment in accordance with theinvention, under different load conditions;

FIG. 2 d a modification of the sports equipment from FIGS. 2 a to 2 c;

FIG. 3 another embodiment of an item of sports equipment in accordancewith the invention, in a lateral view and a front view;

FIG. 4 a a cross-section through a sliding board from FIGS. 1 a to 1 cor a front or rear portion for the sports equipment from FIGS. 2 a to 2d;

FIG. 4 b an upper tension-compression belt for the device from FIG. 4 a;

FIG. 4 c a lower tension-compression belt for the device from FIG. 4 a;

FIG. 4 d edges for the device from FIG. 4 a or 5; and

FIG. 5 a cross-section through a modified front or rear portion for thesports equipment from FIGS. 2 a to 2 d.

DETAILED DESCRIPTION

FIG. 2 a shows an item of sports equipment which is particularlydesigned for sliding on snow or ice. The sports equipment comprises afront portion 10 and a rear portion 20 which are configured to beelongated and the longitudinal axes of which are approximately aligned.The front portion 10 comprises a raised shovel 12 which points in thedirection of motion. The front portion 10 and the rear portion 20 arerespectively formed as snow sliding boards, in particular in the shapeof skis. As shown in FIGS. 2 a to 2 d, the ends 11, 22 of the frontportion 10 and rear portion 20 which point towards each other aredisconnected, but could be connected to a pivoting joint 40 in the formof a hinge, as shown in FIG. 2 d. The pivoting joint can in principlealso be formed in another of the ways described in this document. Thesports equipment shown in FIG. 2 d is in principle structured in thesame way as the sports equipment from FIGS. 2 a to 2 c.

The front portion 10 and the rear portion 20 can be elastically deformedtransverse to their longitudinal axis, i.e. about their transverse axis.The first portion 10 and the second portion 20 are connected by means ofa crosspiece 30, the flexural rigidity of which about the transverseaxis is significantly greater than that of the first and second portions10, 20, such that the crosspiece 30 can also be referred to as rigid.The crosspiece 30 is fastened to the first portion 10 and the secondportion 20 by means of pivoting joints 13, 23. The pivoting joints 13,23 therefore form bearings for the crosspiece 30, which are in principletorque-free, on the first portion 10 and the second portion 20. Ifdesired, a moment could be transmitted from the crosspiece 30 to thefront and/or rear portion 10, 20 by a spring member arranged on thepivoting joints. A damping member could also be provided which actskinematically between the crosspiece 30 and the front portion 10 and/orrear portion 20 and damps pivoting movements between the crosspiece 30and the front portion 10 and/or between the crosspiece 30 and the rearportion 20.

FIG. 2 b shows the sports equipment from FIG. 2 a when under a loadduring turning. The lateral edges which laterally enclose the slidingsurfaces 14, 24 of the first and second portions 10, 20 conform to themotion curve, thus elastically bowing the first portion 10 and thesecond portion 20 such that the sliding surfaces 14, 24 are convex. Thedeformation is caused by the centrifugal force F which the user of thesports equipment exerts on the crosspiece 30. The skier wears a ski bootwhich is fastened to the crosspiece 30 by means of a binding (notshown). Since the force F is arranged in the middle between the frontjoint 13 and the rear joint 23, it is distributed uniformly between thejoints 13, 23, wherein the force F/2 acts on each of the joints. Theline of application of the forces F/2 passes through the respectivedesign point K of the front and rear portions 10, 20. If a moment isapplied to the crosspiece 30, it is not relayed to the front and rearportions 10, 20. Only the forces at the pivoting joints 13, 23 change.

If the skier shifts their centre of gravity towards the rear (FIG. 2 c),the line of application of the force F moves further towards the rearand therefore nearer to the joint 23. The joint 23 is therefore underthe load of a force 3F/4, while the front joint 13 is only under theload of a force F/4. Despite the shift in the line of application of theforce, a moment is not transmitted from the crosspiece 30 to the rear orfront portions 10, 20. The forces at the front joint 13 and the rearjoint 23 also pass through the design point K of the front portion 10and rear portion 20 under these load conditions. This ensures that theedge of the front portion 10 and rear portion 20 remains constantlyconformed to the motion curve and does not rise up.

It can be seen from FIG. 2 d that the crosspiece 30 is connected to thefront portion 10 by a pivoting joint 13 which only permits a pivotingmovement about one axis which is parallel to the transverse axis. Thecrosspiece 30 is also connected to the rear portion 20 by the joint 23.The joint 23 exhibits two pivoting axes which are parallel to each otherand parallel to the transverse axis. An intermediate piece is arrangedbetween the two pivoting axes and performs a pivoting movement relativeto the rear portion 20 and the crosspiece 30 when the rear portion 20performs a pivoting movement relative to the crosspiece 30. Theintermediate piece serves as a length compensator when the front portion10 is pivoted relative to the rear portion 20 by means of the hinge 40.

FIG. 3 shows an alternative item of sports equipment in the form of aroller skate which comprises a boot for accommodating a foot. A firstpivoting joint 13 for a front mount 10 and a second pivoting joint 23for a rear mount 20 are arranged on the lower side of the boot. Thefront mount 10 and the rear mount 20 can be pivoted in relation to theboot, the rigid sole of which forms a crosspiece 30, by means of thepivoting joints 13, 23. The front mount 10 comprises two bearings whicheach rotatably support a roller 15 relative to the front mount 10. Therear mount 20 comprises two bearings which each rotatably support aroller 25 relative to the rear mount 20. The mounts 20, 10 aredisconnected, but could for example be connected via a joint asdescribed in this document; alternatively or additionally, they could beconnected via a spring and/or damping element.

The four rollers 15, 25 shown in FIG. 3 are arranged in alignment in thelongitudinal direction of the crosspiece 30, i.e. in the middle beneaththe boot, as can be seen from the lateral view in FIG. 3.

With conventional inline skates, so-called grinding occurs duringturning, wherein usually four or five rollers arranged in a straightline are moved along the motion curve, generating a relatively highdegree of abrasion on the rollers. The arrangement in accordance withthe invention remedies this, since the rollers 25 of the rear mount 20can conform to the motion curve independently of the rollers 15 of thefront mount 10. The same applies to the mount 10. As can be seen fromFIG. 3, the front mount 10 and the rear mount 20 can only be pivotedabout one axis, i.e. the transverse axis, which is parallel to therotational axes of the rollers 15, 25.

If the front mount 10 and rear mount 20 are connected by means of apivot bearing 40, as shown for example in FIG. 2 d, the rear mount 20 ispreferably connected to the crosspiece 30 by a joint 23 which permitslength compensation. Such a joint is for example shown in FIG. 2 d. Thejoint 23 exhibits two pivoting axes which are parallel to each other andparallel to the transverse axis. An intermediate piece is arrangedbetween the two pivoting axes which performs a pivoting movementrelative to the rear portion 20 and the crosspiece 30 when the rearportion 20 performs a pivoting movement relative to the crosspiece 30.The intermediate piece serves as a length compensator when the frontportion 10 is pivoted relative to the rear portion 20 by means of thehinge 40.

FIGS. 4 a and 5 show a cross-section transverse to the longitudinal axisof a sliding board or ski, for example the ski from FIGS. 1 a to 1 c orthe portions 10, 20 in FIGS. 2 a to 2 d, which are referred to in thefollowing as the ski 100, wherein “ski” is to be understood to also meana sliding board in general.

The ski 100 comprises an upper side which is preferably formed by afaceplate 150 and arranged facing away from a sliding surface 160 on thelower side of the ski 100. A patterned element can be arranged on theupper side and/or the faceplate 150 can comprise a patterned element.The sliding surface 160 is laterally enclosed or defined in thelongitudinal direction of the ski 100 by an engaging edge 130 on eachside, which is preferably formed as a steel edge. Reference isadditionally made to the engaging edge or steel edge described in thisdocument. The engaging edge 130 comprises a multitude of perforations131 which are arranged such that they are spaced from each other by agrid spacing r (FIG. 4 c). The steel edges 130 are fastened directly toa lower tension-compression belt 120 via a connecting layer 135, namelyon the lower side of the lower tension-compression belt 120, i.e. theside which points towards the sliding surface 160. The steel edges 130and the connecting layer 135 each comprise perforations 121 which arecongruent with the perforations 131 of the lower tension-compressionbelt 120. The perforations 121 are arranged along the longitudinaldirection of the ski 100 in the peripheral region of thetension-compression belt 120. The perforations 121, 131, which areformed as elliptical holes whose main axes point in the direction of thelongitudinal direction of the ski 100, therefore form a passage betweenthe upper side of the tension-compression belt 120 and the lower side ofthe engaging edge 130. The engaging edge 130 is shown to beapproximately L-shaped, wherein one limb is parallel to thetension-compression belt 120 and the other limb is approximatelyperpendicular to the first limb. The perpendicular limb preferably formsthe sharpened edge which can engage with the ground surface when the ski100 is in use. The connecting layer 135 can for example be an adhesive.

An upper tension-compression belt 110 is arranged between the upper sideof the ski 100 and the lower tension-compression belt 120 in relation tothe height of the ski 100. The lower tension-compression belt 120 isarranged between the upper tension-compression belt 110 and the slidingsurface 160 in relation to the height of the ski 100.

The upper tension-compression belt 110 comprises a multitude ofperforations 113 which can be configured as elliptical holes with a mainaxis extending in the longitudinal direction of the ski 100. The upperand lower tension-compression belts 110, 120 are each arranged such thatthey are spaced from a neutral fibre when the ski 100 is flexed about aflexing axis transverse to the longitudinal direction and parallel tothe sliding surface 160, wherein the neutral fibre is arranged betweenthe upper tension-compression belt 110 and the lower tension-compressionbelt 120.

The embodiment shown in FIG. 5 substantially differs from the embodimentshown in FIG. 4 a only in that instead of being separate from eachother, the upper and lower tension-compression belts 110, 120 areconnected to each other, namely via one or more connecting portions 115which extend through the neutral fibre and are preferably formed fromthe same material as the upper and lower tension-compression belts 110,120. The upper tension-compression belt 110 and the lowertension-compression belt 120 and the connecting portion 115 are formedfrom one part in the embodiment from FIG. 5. In the embodiment from FIG.4 a, the upper tension-compression belt 110 and the lowertension-compression belt 120 are formed by separate parts. Theconnecting portion 115 is preferably arranged at an angle of between 45°and 90° in relation to the upper tension-compression belt 110 and thelower tension-compression belt 120 and likewise comprises perforations116 which can be shaped in the same way as the perforations of the upperand lower tension-compression belts 110, 120.

A plastic 140 which is injected by means of an injection-moulding methodis injected around the upper tension-compression belt 110 and the lowertension-compression belt 120. The plastic is preferably a thermoplastsuch as for example polyethylene. The plastic can be provided in afoamed or unfoamed form. Other suitable plastics are for examplethermoplasts which are fibre-reinforced, for example glass fibrereinforced. Examples of these include polyamide 6 plastics and polyamide12 plastics which are reinforced with glass fibres. The fibres can forexample be short fibres exhibiting a length of for example 0.1 to 1 mmor long fibres exhibiting a length of for example 1 to 50 mm. Plasticswhich contain long and short fibres can still be injection-moulded. Thefibres can be inorganic or organic reinforcing fibres.

The plastic 140 is additionally arranged or injected in the perforations111, 113, 121, 123 and 131. This results in a substantiallyshear-resistant connection between the tension-compression belts 110,120, the edges 130 and the plastic 140. In other words, the plastic 140,the upper tension-compression belt 110, the lower tension-compressionbelt 120 and the edges 130 form a material composite. The area moment ofinertia or the flexural resistance of the ski 100 about theaforementioned flexing axis can for example advantageously be adjustedin the design of the ski 100 by the distance between thetension-compression belts 110, 120 and the neutral fibre and by thecross-section of the tension-compression belts 110, 120.

The plastic 140 can form the upper side of the ski 100. If a faceplate150 is used, the faceplate can for example comprise projections (notshown) around which the plastic 140 is likewise injected, such that afirm bond between the plastic 140 and the faceplate 150 results. Theseor other projections (not shown) of the faceplate 150 can serve asspacers for the upper tension-compression belt 110, such that theplastic 140 can be dispersed between the faceplate 150 and the uppertension-compression belt 110.

The upper tension-compression belt 110 (FIG. 4 a, FIG. 5) can comprisean opening 112 which is formed as a hole in the planarly formedtension-compression belt, as shown for example in FIG. 4. The opening112 exhibits a larger cross-section than the perforations 111 and 113.The opening 112 is arranged approximately in the middle, i.e. within themiddle third, in relation to the front and rear ends of the ski 100. Inthis example, the opening is likewise elliptical, wherein the main axispoints in the longitudinal direction of the ski 100.

FIG. 4 c shows a lower tension-compression belt 120 in which the frontend is arched upwards and forms a tip of the ski. The rear end of thetension-compression belt 120 is likewise arched upwards slightly, thoughnot as much as the front end. It can be seen in FIG. 4 c that each ofthe left-hand and right-hand peripheral region of thetension-compression belt 120 comprises a multitude of perforations 121which are arranged such that they are spaced from each other by one ormore grid spacings r in the longitudinal direction of the ski 100 andare for example arranged not more than 2 mm from the lateral edge of thelower tension-compression belt 120, in order to advantageously establisha mechanical connection with the injection-moulded plastic. A multitudeof uniformly distributed perforations 123 are arranged between theperforations of the left-hand and right-hand side and are arranged in adistribution up to the region of the upwardly arched front end of thelower tension-compression belt 120. The openings arranged in theupwardly arched region or tip of the ski, which are larger than theperforations 123, 121, can on the one hand save weight in this regionand on the other hand can reduce the strength in this region, sincesomewhat lower mechanism demands are made on the arched region or tip ofthe ski. The openings can therefore be larger than or exhibit adifferent shape to the perforations arranged between the arched regionor tip of the ski and the rear end of the ski 100.

FIG. 4 d shows the left-hand and right-hand edges 130 for the ski 100from FIG. 4 a or FIG. 5, which exhibit a smaller width, extendingtransverse to the longitudinal direction of the ski 100, than the lowertension-compression belt 120 and comprise a multitude of perforations131 which are arranged in a distribution in the longitudinal directionof the edges 130 or the longitudinal direction of the ski 100 and arespaced from each other by one or more grid spacings r. The perforations131 are arranged such that they are congruent with the perforations 121of the lower tension-compression belt 120.

1.-24. (canceled)
 25. An item of sports equipment to be fastened to aperson's foot, the sports equipment comprising: a rolling or slidingmember by means of which the sports equipment can be rolled or slidalong a ground surface, wherein the rolling or sliding member comprisesa front portion and a rear portion, wherein the front portion comprisesa roller or a sliding surface for the ground surface, and the rearportion comprises a roller or a sliding surface for the ground surface,wherein the front portion and the rear portion are connected to acrosspiece.
 26. The sports equipment according to claim 25, wherein endsof the front portion and rear portion which project towards each otherare connected by a joint.
 27. The sports equipment according to claim25, wherein the crosspiece comprises a means by which the sportsequipment can be fastened to a person's foot.
 28. The sports equipmentaccording to claim 27, wherein the means is a boot or a binding withwhich a boot can be fastened to the crosspiece.
 29. The sports equipmentaccording to claim 25, wherein the crosspiece is fastened to the frontportion between an end which points towards the rear portion and itsopposite end via a joint, and is fastened to the rear portion between anend which points towards the front portion and its opposite end via ajoint.
 30. The sports equipment according to claim 29, wherein eachjoint is a pivoting joint which permits a pivoting movement about onepivoting axis only.
 31. The sports equipment according to claim 30,wherein the pivoting axis is transverse to the longitudinal axis of theelongated front and rear portions and parallel to the ground surface.32. The sports equipment according to claim 25, wherein ends of thefront portion and rear portion which point towards each other areconnected by a means which exhibits a lower flexural rigidity about thetransverse axis than the front portion and/or the rear portion.
 33. Thesports equipment according to claim 25, wherein ends of the frontportion and rear portion which point towards each other are connected bya means which forms a flexible or elastic connection, wherein the meanscomprises or is formed from a metallic material, an elastomericmaterial, a leather-like material or a combination thereof.
 34. Thesports equipment according to claim 25, wherein the front portion widensfrom an end thereof which points towards the rear portion to itsopposite end and/or in that the rear portion widens from an end thereofwhich points towards the front portion to its opposite end.
 35. Thesports equipment according to claim 34, wherein the widening isconstant.
 36. The sports equipment according to claim 25, wherein thesliding surface is level or curved, in a prestressed manner, when thesports equipment has no load.
 37. The sports equipment according toclaim 25, wherein the crosspiece exhibits a higher flexural rigidityabout the transverse axis than the front and/or rear portion.
 38. Thesports equipment according to claim 25, wherein the crosspiece isconnected to the front portion by a front fastening means, wherein thefastening means is configured such that the crosspiece can be detachedfrom the front portion, and/or in that the crosspiece is connected tothe rear portion by a rear fastening means, wherein the fastening meansis configured such that the crosspiece can be detached from the rearportion.
 39. The sports equipment according to claim 38, wherein thefront and/or rear fastening means is/are configured as a safety bindingwhich releases the crosspiece for movement when a maximum load isexceeded.
 40. The sports equipment according to claim 25, wherein afront joint or front fastening means is arranged in the middle third orin the rear half of the front portion in relation to the longitudinalaxis and/or a rear joint or rear fastening means is arranged in themiddle third or in the front half of the rear portion in relation to thelongitudinal axis.
 41. The sports equipment according to claim 25,wherein a front end of the front portion and/or a rear end of the rearportion is/are raised.
 42. The sports equipment according to claim 25,wherein one of the front portion and rear portion is connected to thecrosspiece such that it can be pivoted about two parallel pivoting axes,and the other of the front portion and rear portion is connected to thecrosspiece such that it can be pivoted about one pivoting axis.
 43. Thesports equipment according to claim 25, wherein a damping element isarranged between the crosspiece and the front portion and between thecrosspiece and the rear portion.
 44. The sports equipment according toclaim 43, wherein the damping element is made of an elastomeric materialor rubber.
 45. A snow sliding board comprising: an uppertension-compression belt and a lower tension-compression belt which isspaced from the upper tension-compression belt, wherein the upper andlower tension-compression belts are encased in a plastic by means ofplastic injection-moulding, and wherein the upper and/or lowertension-compression belt comprises a multitude of cavities into whichthe plastic is injected.
 46. The snow sliding board according to claim45 wherein the multitude of cavities includes a multitude of ellipticalperforations.
 47. The snow sliding board according to claim 45, whereinthe snow sliding board comprises steel edges which include cavitieswhich overlap and are congruent with the cavities of the lowertension-compression belt, wherein the steel edges are connected to orabut against the lower tension-compression belt.
 48. The snow slidingboard according to claim 45, wherein the snow sliding board comprises afaceplate which includes projections which are anchored in the injectedplastic and/or projections which serve as spacers for the uppertension-compression belt, wherein injected plastic is arranged betweenthe upper tension-compression belt and the faceplate.
 49. The snowsliding board according to claim 45, wherein the uppertension-compression belt and the lower tension-compression belt areseparated from each other by the plastic or are connected by connectingportions.
 50. A method for manufacturing a sliding board, comprising thefollowing steps: a) inserting an upper tension-compression belt, a lowertension-compression belt and steel edges into a die, wherein the steeledges are fastened to the lower tension-compression belt; b) injecting aplastic into the die such that the plastic is injected around the uppertension-compression belt and the lower tension-compression belt.
 51. Themethod according to claim 50, wherein a faceplate for providing at leastone spacer for the upper tension-compression belt is inserted into thedie before the die is closed and preferably before the uppertension-compression belt, the lower tension-compression belt and thesteel edges are inserted.
 52. The method according to claim 50, whereinthe upper tension-compression belt comprises an opening through whichthe plastic is injected below the upper tension-compression belt,wherein the plastic flow is divided in the longitudinal direction of thesliding board towards a front end and a rear end, wherein the dividedplastic flows flow through a multitude of cavities of the upper and/orlower tension-compression belt onto the other side of the upper and/orlower tension-compression belt.